Sparse bounds for discrete spherical maximal functions

Series
Analysis Seminar
Time
Wednesday, February 6, 2019 - 1:55pm for 1 hour (actually 50 minutes)
Location
Skiles 005
Speaker
Dario Alberto Mena – University of Costa Rica
Organizer
Galyna Livshyts
We prove sparse bounds for the spherical maximal operator of Magyar,Stein and Wainger. The bounds are conjecturally sharp, and contain an endpoint esti-mate. The new method of proof is inspired by ones by Bourgain and Ionescu, is veryefficient, and has not been used in the proof of sparse bounds before. The Hardy-Littlewood Circle method is used to decompose the multiplier into major and minor arccomponents. The efficiency arises as one only needs a single estimate on each elementof the decomposition.